Nonoscillating parachute



March 1, 1949. H. G. HEINRICH 2,462,854

NONOSCILLATING PARACHUTE Filed Oct. 30, 1947 BY HI M4,, w

Patented Mar. 1, 1949 UNITED STATES PATENT OFFICE (Granted under the act of March a, 1883, as amended April so, 1928; 370 0. G. 751) The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to parachutes generally and more particularly to improved'non-oscillating parachute constructions for incorporating inherent stabilization into the canopy so that the parachute has no tendency to side slip, oscillate, or spin about its vertical descent axis and if dcflected from a vertical descent axis it will be quickly and positively returned thereto.

A further object is the provision of improved parachute stabilizing means for preventing air passing the skirt portion of the canopy during its descent from following the top contour of the canopy, thereby preventing the variations in negative pressures above the canopy at opposite sides thereof when the canopy is tilted which tend to accelerate the tilt.

A further object is the provision of an improved parachute canopy construction incorporating means for maintaining the descent axis of the parachute vertical and constant, and returning the parachute descent axis to vertical position when deflected therefrom.

A further object is the provision of an improved parachute canopy structure having a comparatively flat cambered cap composed of a plurality of radially arranged longitudinally precambered segments assembled around the canopy vertical descent axis in side by side relation and connected to each other along their juxtaposed edges, each segment having individual air spoiler means at its outer edge and air deflecting means inclining downwardly and inwardly therefrom.

A further object is the provision of shroud line means extending across the top of the canopy along the juxtaposed edges of the cambered segments in which the curvature of the shroud line means across the canopy cap during descent follows somewhat the conventional directions of curvature of the shroud lines in the canopy of a descending conventional fabric parachute.

A further object is the provision of a preformed fabric parachute having a slightly cambered canopy cap composed of adjacent radially disposed segments each cut broadly, and secured together along their opposite edges, to provide individual highly cambered radially disposed portions between the secured edges which extend radially from the canopy descent axis each segment including an end closure member secured across the outer end of the highly cambered portion and inclining downwardly and inwardly to form air deflector means for each segment, and a plurality of shroud lines crossing the canopy cap in contact with the top surface, one line being located between each pair of the adjacent highly cambereo. segments.

A further object is the provision of an improved parachute structure having a circular canopy with a slightly cambered top composed or a plurality of radially disposed highly crowned panels connected together along their opposite edges, each panel terminating in an air spoiler edge with a closure panel inclining downwardly and inwardly therefrom to form an air deflecting surface located immediately below the air spoiler edge, and shroud lines extending radially across the top of the canopy and secured in contact therewith between the highly crowned portions of each adjacent pair of the panels.

Other objects and advantages of my invention will become apparent from the following description, taken in connection with the accompanying drawings in which like reference characters refer to like parts in the several figures. v

Fig. 1 is a side elevation illustrating my improved type of parachute; I

Fig. 2 is a vertical sectional view of the parachute illustrated in Fig. 1, taken on the plane indicated by line 2-2 in Fig. 1, looking in the direction of the arrows;

Fig. 3 is an enlarged fragmentary vertical sectional view taken on the plane indicated by line 3-3 in Fig. 1, looking in the direction of the arrows;

Fig. 4 is a somewhat diagrammatic plan view of one of the top segments and the end closure member.

Fig. 5 is a view similar to Fig. 3, illustrating a slightly modified form of my invention.

Referring to Figs. 1 to 3 the reference numeral I indicates a parachute canopy or cap generally, constructed in accordance with my invention, having a plurality of radially disposed preformed, highly cambered or longitudinally crowned panels or segments 2 which are stitched or otherwise joined together along their opposite edges 2S. The top of the canopy or cap I is preferably circular and slightly cambered between the opposite sides of its periphery as shown in the drawings. A central opening or air vent 3 is \provided for the restricted escape of air entering the interior of the canopy from below during its descent.

The segments or panels 2 are each crowned or cambered throughout their length as indicated, having a greater degree of camber than the crown or camber of the canopy top. Shroud lines 4 are '3 provided,-connected at their lower ends to ring 5, which may in turn be connected to the load 6, or to a parachute harness (not shown) when the chute is to be used with personnel. The shroud lines 4 incline upwardly andgoutwardly from the load to the periphery of the base of the skirt, passing over the top or cap portion of the canopy toward the canopy center in the radial spaces or valleys between the crowned portions of the segments 2. shroud lines are indicated at 4A and also extend radially along and above the seams between the edges of adjacent panels 2 and are preferably secured to the cap of the canopy at a plurality of points between the canopy periphery and its These upper portions of the apex, retaining the shroud lines in position in the canopy portion particularly during the packing and the initial opening of the chute.

The. segments 2 are cut somewhat broadly as diagrammatically shown in Fig. 4, so that when the chute is inflated the top will'be slightly cambered but the individual sections 2 will be cambered to a much greater extent, although the curvature of the top along the seams 23 between the panels, and of course, the direction of curvature of the shroud line portions 4A, will be somewhat similar to the curvature of an inverted catenary or similar to the direction of curvature of the shroud lines in the canopy of a conventional parachute during its descent.

The outer end portions of each of the highly cambered panels 2 is closed by an end panel or a somewhat semicircular closure member 8, secured along its curved edge 8A to the outer edge 2A of the panel 2. These closures 8 are secured across the ends of" the radially disposed crowned panels 2 and the panels are secured together to form the canopy proper. The outer edge of each panel constitutes an abrupt shoulder or air spoiler edge 9, the shoulders '9 taken collectively extend around the periphery of the cap. One of the closure members 8 is disposed directly below the air spoiler edge 9 of each panel, inclining downwardly and inwardly as shown in Figures 1 to 3, presenting an inclined air deflector surface to air passing the base ID of the skirt when the parachute is descending. All of the end closure members or air deflectors 8, taken collectively, form a plurality of air deflector surfaces disposed in an annular downwardly tapered direction, or constitute a truncated conical surface having its axis concentric to the vertical descent axis of the parachute with the air spoiler edge 9 or juncture between the truncated conical portion and the slightly crowned or cambered top preventing air passing the side of the chute during its descent from following the top camber of the canopy, particularly near its periphery.

Under circumstances when a parachute such as illustrated in the drawings is descending vertically all of the inclined panels or end closures 8 deflect the passing air uniformly outward, a certain amount of turbulence occurring at the air spoiler edges 9 and above each of the crowned portions of the panels 2, directly above the air spoiler edges. Since the air deflectors are all at uniform angles of attack around the vertical descent axis when the chute is descending verti cally the chute will be stabilized with no tendency to oscillate, slip, or spin.

When the chute is tilted the airpassing the air spoiler edges 9 sets up substantially the same turbulence above the canopy, but the relative angles of attack of the air deflector panels 8 change, particularly in the vertical plane through 4 the direction of tilt. The angle of attack of the air deflector panel 8 on the downwardly tilted side of the canopy is increased while the attack angle of the panel 8 at the opposite or higher side of the canopy decreases.

The air passing the base of the chute which impinges these deflecting surfaces as the chute descends, immediately causes a relative negative or reduced pressure at the side of the canopy that is high and a relative positive or increased pressure at the low side, resulting in the immediate return of the canopy to a stabilized position with the descent axis vertical.

The shroud lines are extended across the top of the canopy externally thereof following the conventional inverted catenary curvature of the shroud lines of a conventional fabric parachute, eliminating the necessity for extending the shroud lines across the canopy, partly internally I and partly externally, also the removal of the necessity for the form members between the shroud lines and the seams of the canopy, as set forth in -my co-pending application for Guide surface parachutes.

In the modified form-as shown in Fig. 5 the same reference numerals are used for parts which are similar to the other figures. The end closure members 8.are each provided with an air vent 8V located in the top portion thereof, adjacent the air spoiler edge 9. In the descent of this parachute some of the air which passes into the canopy from below is permitted to escape through the opening 8V and being somewhat jetlike tends to increase the turbulence directly above the center of the panel 2 and above its air spoiler edge 9, thus increasing the turbulence uniformly around the periphery of the chute, even when it is inclined far off of its vertical descent axis. The air which impinges the air deflection surfaces directly below the openings 8 will quickly restore the chute to its vertical descent axis.

The drawings are for illustrative purposes and it is understood that the patentable scope and novelty of my invention is only limited by the scope of the appended claims.

I claim: I

1. In a parachute of the class described, a canopy having a vertical descent axis and a relatively flat cambered top composed of a plurality of radially disposed preshaped'panels, each panel having a relatively high transverse camber extending longitudinally of the panel, and air deflector closure panels secured across the outer ends of the first mentioned panels and inclining downwardly and inwardly therefrom toward the vertical descent axis of the canopy to form air spoiler edges around the periphery of the canopy, and forming, lateral air deflectors around the canopy periphery for laterally deflecting the airpassing the base of the canopy during its descent.

2. In a parachute of the class described, a canopy having a relatively fiat cambered top composed of a plurality of radially disposed panels having their adjacent edges connected, said panels each having a relatively high cambered intermediate portion between the connected edges extending longitudinally, a closure panel inclining downwardly and inwardly from the outer end of each radial panel to close the outer end of the inverted trough formed by the highly cambered portion, forming an abrupt air spoiler edge at the outer end and top portion of the highly cambered radial panel and constituting a fixed air deflector inclining inwardly below said spoiler edge, for outwardly deflecting air passing the base of the canopy during its descent to obtain predetermined radial thrust on said panel toward the axis of the parachute.

3. A canopy having a vertical descent axis and formed from a plurality of radially disposed se ments or panels connected together along their adjacent edges, each panel being cambered transversely along its longitudinal center to form an inverted air trough, and a closure panel secured to the outer end of the panel across the end of said inverted air trough to retard the outward passage of air therethrough said closure panel inclining downwardly and inwardly from the outer edge of the base of the inverted air trough toward the vertical descent axis of the canopy.

4. In a parachute of the class described, a canopy having a relatively flat camber, composed of a plurality of radially disposed panels connected together along their opposite edges, said panels each being longitudinally crowned between their connected edges, an end closure panel secured across the outer end of each of the longitudinally crowned portions of the panels, and inclining inwardly and downwardly to form a tapered air deflecting surface at the outer end of the panel and an air spoiler edge at the juncture between the radial and inclined panels.

5. Apparatus as claimed in claim 4 in which the inclined panels are provided with vent openings therethrough located directly below the air spoiler edge to direct air, escaping through the vent openings from the interior of the canopy, outwardly across the air spoiler edges.

6. In a parachute of the class described a canopy having a relatively flat camber terminating at its periphery in an air spoiler edge, and a plurality of fixed air deflector surfaces disposed uniformly around the canopy vertical descent axis and inclining downwardly and inwardly from the air spoiler edge to form air deflector surfaces disposed in equal angle of attack positions, relative to the vertical descent axis of the faces, and shroud lines secured across the top of the canopy between the said adjacent inverted troughshaped pockets.

7. In a parachute of the class described a circular canopy having a vertical descent axis and a relatively flatly cambered top having an air spoiler edge at its periphery, said canopy comprising a plurality of flexible preformed segmental panels secured together along their adjacent edges, each panel having a relatively high transverse camber extending from its inner end to its outer end to form an inverted radial air collecting trough within the canopy and facing downwardly, an air deflecting closure member secured across the outer end of each air collecting troughs having a plane surface inclining downwardly, and inwardly from the air spoiler edge and top peripheral portion of the canopy toward the central axis of the canopy to form air deflectors having fixed and equal angle of attack positions around the skirt of the canopy relative to the vertical descent axis of the canopy to laterally deflect the air passing the base of the skirt of the canopy, and when the canopy is tilted during descent, to dispose the air deflector at the low side of the canopy in the plane of tilt at an increased attack angle position to the passing air and the air deflection at the higher opposite side in the plane of tilt at a lesser angle of attack position the passing air, and load sustaining shroud lines extending across the canopy top between the inverted trough shaped portions and secured to the canopy top between its periphery andcentral axis.

HELMUT GUSTAV HEINRICH.

REFERENCES CITED The following references are of record in the flle of this patent:

UNITED STATES PATENTS Number Name Date 2,089,140 Tricau Aug. 3, 1937 2,379,758 Smith July 3, 1945 FOREIGN PATENTS Number Country Date 36,142 France Jan. 6, 1930 (Addition to 645,171) 

